In internal combustion engines utilizing electronic components, such as an electronic fuel pump controller, the components are deleteriously affected when exposed to environmental extremes in temperature and vibrations. By reason of this fact, it has heretofore normally been necessary to mount such components in somewhat remote locations on the engine, notwithstanding that from a space limitation consideration it would be more desirable to mount such components directly on the exterior of the fuel pump body. Furthermore, because of the size and complexity of prior assemblies of this general type, attachment thereof directly to the pump body could not be readily achieved without requiring substantial modifications being made to the engine and/or fuel pump body. Prior assemblies because of inherent design characteristics oftentimes were awkward and difficult to mount; were ineffective in cooling and dampening vibrations of the controller components; and required an inordinate amount of maintenance and servicing.